A Perspective on Applications of Schiff Base Metal Complexes in Photovoltaic And Light Emitting Devices: Tunability And Effect Of Structural Modifications

Abstract

Schiff base metal complexes have been widely explored due to their high utlities in a diverse range of areas, including therapeutic, optical/electrochemical sensors, and environmental remediation. Their unique photophysical and electrochemical properties resulting from the presence of imine groups and a higher degree of conjugation, along with their enhanced stability make them a class of efficient photosensitizers for the development of Dye-Sensitized Solar Cells (DSSCs). Various Schiff base complexes are also utilized to develop an effective electrolyte system with the desired redox properties. Their diverse emissive behavior, which has been conveniently utilized in the emissive layer of a number of Organic Light-Emitting Diodes (OLEDs). Schiff base metal complexes based OLEDs can be fluorescence-dependent as well as phosphorescence-dependent. Schiff base metal complexes of heavy transition metals, especially those involving d6 and d8 metal ions, have gained significant attention as phosphorescent emitters. Minute structural modifications in the Schiff base ligands in the complexes can alter the emission color, brightness, and efficiency of the OLED. Although a plethora of articles are easily accessible that present thorough reviews on the applications of these complexes and their unique characteristics. However, discussions on the applicability of Schiff base complexes as effective alternative materials in photovoltaic devices, as well as light-emitting devices, are rare. This perspective comprehensively discusses the advancements in the Schiff base metal complex-based DSSCs and OLEDs, with special emphasis on their electrochemical properties. Moreover, the review highlights the impact of various substituents, structural properties and molecular interactions of Schiff base complexes on the performance of the DSSCs and the different types of OLEDs.